Re: visibility map corruption

On Thu, Jul 8, 2021 at 07:35:58AM +0200, Drouvot, Bertrand wrote:
> Thanks for having looked at it.
>
> It looks good to me, but i have one question:
>
> +    printf(_("  -u, --oldest-transaction-id=XID  set oldest transaction
> ID\n"));
>
> and
>
> +                   if (!TransactionIdIsNormal(set_oldest_xid))
> +                   {
> +                        pg_log_error("oldest transaction ID (-u) must be
> greater or equal to %u", FirstNormalTransactionId);
> +                        exit(1);
> +                   }
>
> I am wondering if we should not keep my original proposal "oldest unfrozen
> transaction" (as compare to "oldest transaction") in both output to:
>
> - make the wording similar with what we can found in StartupXLOG():
>
>     ereport(DEBUG1,
>             (errmsg_internal("oldest unfrozen transaction ID: %u, in
> database %u",
>                              checkPoint.oldestXid,
> checkPoint.oldestXidDB)));
>
> - give the new  "-u" a sense (somehow) from a naming point of view.
>
> What do you think?

I was wondering about that too. We don't use the term "unfrozen" in the
pg_control output, and only in a few places in our docs. I added the
word "unfrozen" for the -u doc description in this updated patch ---
not sure how much farther to go in using this term, but I am afraid if I
use it in the areas you suggested above, it will confuse people who are
trying to match it to the pg_control output.

--
Bruce Momjian <bruce(at)momjian(dot)us> https://momjian.us
EDB https://enterprisedb.com

If only the physical world exists, free will is an illusion.